12 Vulpeculae
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Vulpecula |
| Right ascension | 19h 51m 04.1083s |
| Declination | +22° 36′ 36.173″ |
| Apparent magnitude (V) | 4.928±0.015 (4.78 - 4.97) |
| Characteristics | |
| Spectral type | B2.5V |
| Apparent magnitude (U) | 4.104±0.020 |
| Apparent magnitude (B) | 4.759±0.017 |
| Variable type | Be star |
| Astrometry | |
| Radial velocity (Rv) | −24.90 km/s |
| Proper motion (μ) | RA: 23.404±0.068 mas/yr Dec.: −15.797±0.099 mas/yr |
| Parallax (π) | 5.1710±0.1070 mas |
| Distance | 630 ± 10 ly (193 ± 4 pc) |
| Absolute magnitude (MV) | −1.52 |
| Details | |
| Mass | 6.8 M☉ |
| Luminosity | 963 L☉ |
| Surface gravity (log g) | 3.36 cgs |
| Temperature | 18,859 K |
| Metallicity [Fe/H] | −0.01 dex |
| Rotational velocity (v sin i) | 195 km/s |
| Other designations | |
| 12 Vul, V395 Vul, BD+22°3833, FK5 3585, GC 27493, HD 187811, HIP 97679, HR 7565, SAO 87813 | |
| Database references | |
| SIMBAD | data |
12 Vulpeculae is a star in the northern constellation of Vulpecula, located approximately 630 light years away based on parallax. It has the variable star designation V395 Vul; 12 Vulpeculae is the Flamsteed designation. This object is visible to the naked eye as a faint, blue-white hued star with a baseline apparent visual magnitude of 4.928. It is moving closer to the Earth with a heliocentric radial velocity of -25 km/s.
This is a variable Be star with a stellar classification of B2.5V; its brightness ranges from magnitude 4.78 down to 4.97. As is true with other Be stars, it has a high rate of rotation with a projected rotational velocity of 195 km/s. The star has 6.8 times the mass of the Sun and is radiating 963 times the Sun's luminosity from its photosphere at an effective temperature of 18,859 K.